Cable tensioner for a periprosthetic repair system

ABSTRACT

A system, devices and methods are provided for facilitating stabilization of periarticular fractures. The system includes a compression plate and one or more of a cerclage cable for encircling the bone and securing the compression plate to the bone, a crimp lug for securing the cable in tension relative to the bone and/or a plate, and a supplemental plate coupled to the compression plate and adapted to receive bicortical or unicortical bone screws to further secure the compression plate relative to the bone. In addition, the system includes a cable tensioner for temporarily retaining the cable in tension and then applying a tension to the cable until a desired compression is effected between a plate and bone and while a cable retaining structure is secured to the cable to retain the applied tension on the cable. Also provided is a jig for use with plates for minimally invasive fracture stabilization.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to surgery. More particularly, the presentinvention relates to plating systems and tools, and specifically platingsystems and tools for treatment of periarticular fractures.

2. State of the Art

Fractures around implants pose unique fixation challenges. The originalplacement of the implant may predispose the bone to later fracture, asthe long-term presence of the implant may change the structure of thesurrounding bone and increase susceptibility to fracture. In addition,the implant itself may interfere with healing or the placement of otherfixation devices.

This is particularly a problem around the femur where a femoralcomponent of a hip replacement prosthesis may be implanted. Further, asthe population ages and the indications for joint replacement increase,the number of implants in the femur is increasing. With increased hipjoint replacement, the number of fractures associated therewith has alsoincreased. Once a fracture occurs, treatment is complicated byosteoporosis, defects in the bone, and the presence of the implant. Inparticular, stems, rods, screws, and methylmethacrylate may block themedullary canal, preventing intramedullary fixation of fractures. Stemsand rods also block screw fixation through the medullary canal to holdfracture stabilization plates on bone. The techniques for treatingperiprosthetic fractures are generally more difficult, with limitedoptions.

Nevertheless, essentially all periprosthetic fractures require sometreatment. Stable nondisplaced fractures may only require protectedweight-bearing or cast/brace immobilization. However, most unstableperiprosthetic implant fractures require surgical stabilization and/orimplant replacement to restore function.

Surgical stabilization includes plating to secure the adjacent sectionsof the fractured bone to facilitate healing, which may occur with orwithout implant replacement.

It must be appreciated that standard plating includes attaching astabilization plate to the bone with screws. Given the inability to passa screw bicortically through the bone and the overall poor quality ofthe bone, alternative means of fixation are used to couple the plate tothe bone. Most typically, such fixation includes unicortical screws thatare inserted into the bone in a spatial distribution that does notinterfere with the implant and cerclage cables that are wrapped undertension around the bone. The ends of the cable are crimped together witha crimp to maintain tension on the cable at a specific force. However,current tools for working with securing the cable make application ofthe system difficult. In particular, existing cable tensioners require atemporary tension holder as well as a separate cable tensioner, and bothinstruments must be operated together and used to tension the cable. Inaddition, after tension is applied and fixed to the cable, even a smallamount of movement between the cable, the plate and the anatomy cancause significant reduction in tension on the cable and release ofcompression between the plate and the bone.

SUMMARY OF THE INVENTION

In accord with the invention, a system is provided for facilitatingstabilization of periarticular fractures. The system includes acompression plate and a cerclage cable for encircling the bone andsecuring the compression plate to the bone. The cable has a ball orother structure functioning as a stop at one end, and a free end.

More particularly, the compression plate includes a plurality of screwholes preferably including at least one threaded screw hole extendingbetween an upper surface of the plate and an opposing bone contactinglower surface of the plate, and at least one compression slot alsoextending between the upper and lower surfaces of the plate.

In one embodiment, the compression plate includes screw-receiving tabsthat are configurable by the surgeon at the time of implantation. Thetabs may be integrated with the plate. Additionally or alternatively, inaccord with another preferred aspect of the invention, the system mayalso include one or more supplemental plates usable over the compressionplate. The supplemental plates are short bent plates having a bridgeportion with a screw hole, and which can be positioned in a transverse(lateral) configuration over the compression plate and secured theretoby insertion of a set screw through the hole in the supplemental plateand into threaded engagement with the compression plate therebelow. Thesupplemental plate has a plurality of screw-receiving tabs that areconfigurable by the surgeon at the time of implantation. In addition,the compression plate may be provided with a longitudinally displacedrecesses on opposing lateral side of plate located in alignment with thethreaded screw holes. When a supplemental plate is attached to thecompression plate, portions of the supplemental plate fit into therecesses on the lateral sides of the plate to lock the orientation ofthe supplemental plate to the compression plate; i.e., prevent rotationof the supplemental plate relative to the compression plate.

In accord with another aspect of a compression plate according to thesystem, the compression plate includes an integrated cable securingstructure. In an embodiment, the cable securing structure includes twocable passages extending in a widthwise direction through the plate. Thefirst passage includes an opening of a sufficiently large diameter topermit a portion of the cable to pass therethrough. The second passageincludes an opening of a sufficiently large diameter to permit a portionof the cable to pass therethrough but sufficiently small diameter toretain a ball end of the cable. In use, the cable is first fed throughthe second opening until the ball end of the cable is retained at theopening thereof, the cable is wrapped about the bone, the cable isinserted into the first passage and drawn into tension to cause thedesired compression of the plate against the bone, and then a crimp isapplied to the end of the cable extending through the first passage toretain the cable in tension relative to the plate. In accord with oneaspect of the invention, the second passage is defined within acantilevered resilient beam (deflection beam) that adds elasticity tothe tensioned cable. The deflection beam is preferably paired withindicia on the plate such that the beam and indicia together indicate atleast a relative amount of tension applied to the cable. The beam andindicia are preferably visible under fluoroscopy facilitatingascertainment of the cable tension both during and after the surgicalprocedure.

In another embodiment, the cable securing structure includes first andsecond passages extending widthwise through the plate and an integratedresilient clamp which can be clamped toward a closed position with a setscrew adjacent the second passage to reduce the diameter of the secondpassage. The integrated resilient clamp preferably comprises adeflectable member unitary with the plate and which when clamped closedwith the set screw to secure the cable preferably is not caused toexceed the elastic limits of the plate material and does not undergoplastic deformation. In use, the cable is first fed through the firstpassage until the ball end stops its progress, the cable is wrappedabout the bone, the cable is inserted into the second passage and drawninto tension to cause the desired compression of the plate against thebone, and then the set screw is rotated to clampingly secure the cablerelative to the plate.

In accord with another aspect of the invention, the system may includediscrete crimp lugs formed separate from the plate and provided forguiding a cable, and securing the ends of the cable relative to eachother in tension. Each crimp lug includes a head with two eyeletsextending through a wall thickness of the lug, and a plate retainingfeature that permits the positioning of the crimp lug within a screwhole of the compression plate. The retaining feature preferably permitsa crimp lug to be retained through frictional interference, threading,or other mechanical interference with the plate at the screw hole. Theretaining feature may be resiliently deformable for insertion into ascrew hole. Before the ends of the cable are secured, a discrete crimplug is self-engaged within a screw hole, and maintains such engagementregardless of the orientation of the plate and while the surgeon worksto feed the cable through the eyelets. Once cable is advanced throughthe eyelets, the head of the crimp is plastically deformed to retain thecable in tension about the bone and plate.

In accord with yet another aspect of the invention, the system mayinclude discrete crimp lugs formed separate from the plate and providedwith retaining structure for attachment of the lug directly to the boneindependent of a plate. Each such crimp lug includes a head with twoeyelets extending through a wall thickness of the lug. The retainingstructure is preferably a threaded shaft or a sharpened post, such as atack end or nail end, each permitting the lug to be driven into the bonefor temporary or permanent fixation. The lug can then be used in astandard manner, permitting cable ends to be advanced through therespective eyelets, drawn into tension about a plate and bone, and thenretained in tension by plastic deformation of the head of the lug.

In addition, the system includes an instrument for tensioning a cableadvanced through the eyelets of an integrated cable securing structure,a separate cable crimp lug, or used in association with any otherstructure for stabilization of a periarticular or other fracture. Thecable tensioner is a single instrument having a proximal gear box and adistal tube. In a preferred embodiment the gear box includes a wormscrew having a torque driver socket, the worm screw in gear-engagementto a drive gear, a cable pulley rotationally fixed to the drive gear,and a collet and a locking knob in rotational alignment and fixationrelative to the pulley, such components together housed in or on ahousing. The pulley has a plurality of grooves in the circumferentialtrack of the pulley. The tube has a distal end pre-formed with a gentlecurve and a proximal end secured at the housing.

In operation of the cable tensioner, no assembly of the cable tensioneris required nor is it required to be used with any other instrumentcomponent. The cable free end is passed through a first passage in theplate or eyelet of the crimp lug, positioned around the bone and thenpassed though the second passage or eyelet in the plate or crimp lug.The free end is then inserted into the curved distal end of the tensiontube of the cable tensioner and advanced towards/through the cabletensioner housing. The free end of the cable is pulled and the cabletensioner is advanced towards the plate or crimp lug until the tensionertube contacts the plate or crimp lug. The free end of the cable is thenadvanced around a portion of the pulley, through one of the grooves inthe pulley, and then into the respective central holes of the pulley,the collet and the locking knob. The cable is manually pulled taughtuntil there is no cable slack between the tube and the pulley. Then thelocking knob is rotated until the cable is retained relative to theproximal housing of the tensioner. A driver is inserted into the wormscrew end and engaged with a driver socket, and as the driver is rotatedin a first direction the worm gear rotates to “spool” the cable onto thepulley. The portion of the cable extending around the bone decreases andcompresses the plate onto the bone. Also, if the driver is rotated in anopposite second direction, the length of cable extending about the boneis increased, the tension on the cable is decreased, and the appliedcompression between the plate and bone is decreased. Once the cabletensioner is operated to apply the desired tension to the cable, thecable can be appropriately secured relative to the plate, lug, or otherstructure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a short grip-type compression plateapplied at the trochanter of the femur.

FIG. 2 is a side view of the grip-type compression plate of FIG. 1applied at the trochanter of the femur.

FIG. 3 is a front view of another grip-type compression plate located ona femur.

FIG. 4 is a perspective view of yet another grip-type compression platein association with supplemental plates.

FIG. 5 is an enlarged perspective view of a portion of the shaft of thecompression plate of FIG. 4, illustrating a supplemental plate and anintegrated cable retaining structure.

FIG. 6 is a perspective view of a further grip-type compression plate inassociation with two different types of supplemental plates.

FIG. 7 is a view similar to FIG. 6, illustrating a cerclage cable withinthe integrated cable retaining structure and with the supplemental plateremoved.

FIG. 8 is a side elevation view with a partial section of the plate withcable of FIG. 7.

FIG. 9 is a perspective view of a compression plate with anotherintegrated cable retaining structure and cable retained therein.

FIG. 10 is a perspective section view of a compression plate with yetanother integrated cable retaining structure.

FIG. 11 is a perspective view of a compression plate with even yetanother integrated cable retaining structure.

FIG. 12 is an enlarged partial section perspective view of a portion ofFIG. 11.

FIG. 13 is a perspective view of another compression plate shownrelative to a distal femur, and provided with a crimp lug.

FIG. 14 is a perspective view of one embodiment of a crimp lug.

FIG. 15 is a perspective view of the crimp lug of FIG. 14 inserted intoa screw hole in the compression plate of FIG. 13.

FIG. 16 is a transverse section view through line 16-16 in FIG. 15.

FIG. 17 illustrates the crimp lug securing a cerclage cable.

FIG. 18 is a perspective view of a first embodiment of a crimp lug forimplantation in bone.

FIG. 19 is a perspective view of a second embodiment of a crimp lug forimplantation in bone.

FIGS. 20 and 21 are proximal end perspective view of a cable tensioner.

FIG. 22 is an assembly view of the cable tensioner of FIGS. 20 and 21.

FIG. 23 is a perspective view of a wound cerclage cable provided with aspring according to an embodiment of the invention.

FIG. 24 is a perspective view illustrating the cerclage cable of FIG. 23relative to an integrated cable retaining structure of a plate.

FIG. 25 is a view similar to FIG. 24 shown with a cross-section throughsecond cable passage of the plate.

FIG. 26 is a side elevation view with a partial cross-section throughthe plate of FIGS. 24 and 25.

FIG. 27 is an assembly view of a tool for manipulating crimp lugs.

FIG. 28 is a perspective view of the tool of FIG. 27 provided with acrimp lug.

FIG. 29 is a perspective view of a cable tensioner shown applying acerclage cable about a bone and plate.

FIG. 29A is a perspective view of a cable tensioner shown applyingmultiple cerclage cables about a bone and plate.

FIG. 30 is a broken enlarged portion of a tension gauge and cam lock ofthe cable tensioner of FIG. 29.

FIG. 30A is a longitudinal section view of the tension gauge and camlock of the cable tensioner of FIG. 29.

FIG. 31 is a top view of a distal femoral plate according to theinvention.

FIG. 32 is a bottom perspective view of the distal femoral plate of FIG.31.

FIGS. 33 through 36 are schematic section views of a plate and bonescrew illustrating the operation of a dynamic compression hole accordingto the invention.

FIG. 37 is a schematic perspective view of a first position of a bonescrew relative to a dynamic compression hole of a bone plate accordingto the invention.

FIG. 38 is a schematic perspective view of a second position of a bonescrew relative to a dynamic compression hole of a bone plate accordingto the invention.

FIG. 39 is a top perspective view of another distal femoral plateillustrating an alternate arrangement of dynamic compression holes inthe plate.

FIG. 40 is a perspective view of a screw implantation jig assembled tothe plate of FIG. 39.

FIG. 41 is a perspective view of the screw implantation jig assembled tothe plate and with tissue penetration and drill guide tools coupled tothe jig and plate.

FIG. 42 is a perspective view of a distal end of the locking guide forlocking the jig relative to the bone plate.

FIG. 43 is a perspective of an outer sleeve for use with the jig of FIG.40.

FIG. 44 is a side elevation of a drill guide for use with the jig ofFIG. 40.

FIG. 45 is a longitudinal section view of the drill guide of FIG. 44.

FIG. 46 is a perspective view of a distal end of the drill guide of FIG.44.

FIG. 47 is a distal end view of the distal end of the drill guide ofFIG. 44.

FIG. 48 is a broken section view of the outer sleeve positioned adjacentthe upper surface of the plate, and the drill guide in a firstrotational orientation extended through a dynamic compression hole.

FIG. 49 is a broken section view of the outer sleeve positioned adjacentthe upper surface of the plate, and the drill guide in a secondrotational orientation locked relative to the plate at the dynamiccompression hole.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the human body and components of the system describedherein which are intended to be implanted in the human body, the terms“proximal” and “distal” are defined in reference to the location atwhich a limb is connected to the torso, with the term “proximal” beingthe end of the limb, bone, or plate closer to the torso, and the term“distal” being the end of the limb, bone, or plate further from thetorso. In addition, the term “lower” and “upper” in reference to platesurfaces are designations in which the lower surface is that surfacecloser to or seating on the bone, and the upper surface is that surfaceopposite the lower surface. Further, with respect to a plate, the terms“length”, “width” and “thickness” are relatively transverse dimensionswith the length being the dimension along the longitudinal axis of aplate, the width is a laterally transverse dimension to the length, andthe thickness is a dimension extending between the upper and lowersurface.

With reference to instruments of the system that are hand-held by auser, the terms “proximal” and “distal” are defined in reference to theuser's hand, with the term “proximal” being closer to the user's hand,and the term “distal” being further from the user's hand.

In accord with the invention, a system is provided for facilitatingstabilization of a periarticular fracture. The system includes acompression plate and one or more of the following: a cerclage cable forencircling the bone and securing the compression plate to the bone, abicortical bone screw for extension from one side of the bone, throughthe medullary canal, and into the other side of the bone, and aunicortical bone screw for extension at least partly into the bone.

Referring to FIGS. 1 and 2, one compression plate according to thesystem of the invention is a short grip plate 10. The short grip plate10 is designed for placement over and reattachment of the greatertrochanter 12 of the proximal femur 14 after the greater trochanter isremoved in an osteotomy procedure. To secure the re-positioned greatertrochanter to the remainder of the femur for proper healing, theproximal end of the grip plate includes hooks 16 that can be positionedaround the greater trochanter and embedded into the femur bone using animpactor instrument (not shown). At a portion of the plate for placementat the inferior portion 18 of the greater trochanter (i.e., at orproximate the intersection with the diaphysis 20 of the femur) the platepreferably includes one or more spikes 22 at its lower surface 24 thatcan also be embedded in the bone to aid in at least temporary fixationof the plate on the femur, e.g., while the plate is more permanentlysecured to the bone with cerclage cables 26 and/or screws 36. The cables26 are preferably non-elastic metal cables, constructed from, e.g.,titanium, stainless steel or cobalt chrome, and encircle a portion ofthe bone 14, and placed under tension to apply a stabilizing compressiveforce between the plate and bone. The spikes 22 also provide rotationalstability of the plate 10 on the bone even after the plate is secured bythe cables 26. In fact, the tension on the cables 26 around the plate 10and bone forcibly embeds the spikes 22 further into the bone forincreased stability.

The short grip plate 10 includes a portion between the hooks 16 andspikes 22 in which the lower surface is concave in the longitudinaldirection such that the plate accommodates the convex anatomy of thegreater trochanter 12. In a shorter plate, as shown, such concavecurvature may occur over substantially the entire length of the plate.In a longer grip plate, such as plate 10′ shown in FIG. 3 and describedbelow, such concave lower surface curvature is generally provided onlyalong the proximal portion of the plate, with the remainder of the platesubstantially straighter to conform to the diaphyseal portion of thefemur.

In accord with one aspect of the invention, the grip plate 10 includesat least one pair of screw tabs 28 extending transversely from theopposing (lateral) sides of the plate. The screw tabs 28 each include aring 30 defining a threaded screw hole 32 attached to the plate by abendable bridge 34. The threaded screw hole is for receiving andengaging the threaded head of bone fastener 36. The tabs 28 can be bentabout the bridges 34 and thereby manipulated in orientation eitherbefore or after the plate is positioned on the bone by using drillguides installed in threaded screw holes of the rings, as described indetail in U.S. Pat. Nos. 7,935,126 and 8,192,472, and US Pub. No.20100069966A1, each of which are hereby incorporated by reference hereinin their entireties. This allows the axial orientation of the screw holeto be customized for the particular fixation and particularly based onthe location of the osteotomy, the medullary canal content, or otherconsiderations.

The grip plate 10 can be provided in several sizes and lengths. Asdiscussed, FIGS. 1 and 2 illustrate a short grip plate used locallyabout the greater trochanter. For trochanters of different sizes, platescan be provided in having a range of dimensions between the proximalhooks. Referring to FIG. 3, a longer grip plate 10′ is shown whichincludes a proximal head 40′ for placement at the trochanter 12 and adistal shaft 42′ adapted for extension along the diaphysis 20 of thefemur. The plate shaft 42′ includes a plurality of pairs of alignedscrew tabs 28′ extending transversely from opposing sides of the platewhich function in a similar manner to screw tabs 28. That is, each screwtab 28′ has a threaded hole for receiving and engaging the threaded headof bone fastener. In addition, the screw tabs 28′ are preferablyreconfigurable with the use of drill guides as discussed above. It iswithin the scope of the invention to provide a plate that includes screwtabs both along the head and shaft of the bone plate, thus combiningfeatures of plates 10 and 10′.

Turning now to FIG. 4, another embodiment of a grip plate 110, generallysimilar to plates 10, 10′, is shown. Grip plate 110 is a long platehaving tabs 128 at its head portion 140 for engagement with thetrochanter 12 and an elongate shaft 142 for extension along thediaphysis 20 of the femur 14. The grip plate 110 includes a longitudinalaxis A₁, upper and lower surfaces 172, 124, and opposing longitudinalsides 125 a, 125 b extending between the upper and lower surfaces. Thegrip plate includes a plurality of longitudinally spaced apart threadedscrew holes 148 along its shaft 142. In accord with another aspect ofthe invention, the grip plate 110 includes one or more supplementalplates 150 positioned over and couplable to the grip plate 110 at thethreaded screw holes. Each supplemental plate 150 is a short bent‘bridge’ plate having an upper portion 152 and first and second lowerportions 143 each with screw receiving tabs 158. The bridge plate 150can be positioned in a transverse (lateral) configuration over thecompression plate 110, and the upper portion 152 is provided with ascrew hole 154 at which it can be secured to the compression plate byinsertion of a set screw 156 through hole 154 and into the threaded hole148 of the compression plate 110 therebelow. The threaded hole 148 ispreferably tapered. The set screw 156 preferably has a taperedcollet-like split shaft, such that when the set screw 156 is advancedinto the screw hole 148, it can collapse in a radial direction tofacilitate locking relative to compression plate 110. Thescrew-receiving tabs 158 at the lower portions include preferablythreaded holes for receiving a bone screw with a threaded head or anon-threaded head, and are bendable about a reduced width span 159 suchthat the axial orientation of the threaded holes can be reconfigured bythe surgeon at the time of implantation, e.g., with the drill guidesreferenced above. As shown in FIG. 6, supplemental plates may beprovided with larger tabs 158 for receiving larger headed screws, suchas provided with bicortical screws 160 that can extend across the cortexof the diaphysis, or smaller tabs 158′ for receiving the smaller headedscrews, such as unicortical screws 160′, or a combination ofsupplemental plates to accommodate both types and various sizes ofscrews. Supplemental plates with such different tab sizes can be coupledat different threaded holes of the compression plate. As seen best inFIGS. 4 and 5, the plate 110 is preferably provided with a peripherallip 162 extending along the opposing sides 125 a, 125 b adjacent thelower surface 124 of the plate, with such lip provided withinterruptions 164 located in alignment with threaded screw holes 148that define recesses 165 along the sides of the plates. Theinterruptions 164 have a length corresponding to the widthwise dimensionof the supplemental plate across the lower portions 143. When asupplemental plate 150 is attached to the compression plate, the lowerportions 143 of the supplemental plate 150 fit between the interruptions164 such that the lip 162 surrounds the supplemental plate at proximaland distal sides thereof to further lock the rotational orientation ofthe supplemental plate 150 relative to the grip plate 110. Even withouta lower lip, such lateral locking recesses 165 can be defined in thesides of the plate, as shown in FIG. 7.

Turning now to FIGS. 5, 7 and 8, the compression plate 110 includes anintegrated cerclage cable securing structure. The cerclage cable 26 hasa ball 26 a or other structure functioning as a stop at one end, and anopposite free end 26 b. The plate 110 has two transverse cable passages166, 168 extending through the width of the plate. The first transversepassage 166 allows passage of the free end but restricts passage of thestop end 26 a of the cable 26. The second transverse passage 168 alsoallows passage of the free end 26 b of the cable therethrough. A slot170 is provided within the plate 110 extending through the secondpassage 168 and into the first passage 166. The slot 170 also opens upto the upper surface 172 of the plate at 170 a. As such, the slot 170defines a gap between the upper plate surface 172 and the portion of theplate beneath the slot 170. The slot 170 may be formed, e.g., via laseror electric discharge machining (EDM). The plate at the end of the slotopposite open end 170 a, i.e., over the first passage 166, defines adynamic hinge 171 at one end of the gap. A set screw hole 174 is definedthrough the upper plate surface, 172, the slot 170, and the portion ofthe plate beneath the slot 170, at a location between where the slotopens at 170 a to the upper surface 172 and the second passage 168;i.e., it is longitudinally offset from the second passage 168. Theportion of the set screw hole 174 beneath the slot 170 is threaded. Aset screw 176 is partially threaded into the set screw hole 174. Adynamically hinged clamp 178 is thus formed. As the set screw 176 isrotated, the diameter of the second passage 168 is modified indimension, with seating the set screw 176 causing the clamp 178 todecrease the gap and close down on the second passage 168. While thehinge clamp 178 preferably is deformable about a dynamic hinge definedat the first transverse passage 166, in an alternate construction, thehinge may be defined via a different through passage. By way of example,a hinge through passage may be longitudinally displaced between thefirst and second passages 166, 168.

In use, the cable 26 is first fed through the first passage 166 untilthe ball end 26 a of the cable is retained at the opening 166 a thereof.The opening 166 a of the first passage 166 may include a countersink toat least partially recess the ball end 26 a. The free end 26 b of thecable is then circled about the bone 14, and inserted into and throughthe second passage 168. The cable 26 is drawn into tension, preferablyusing the instrument 710 described below (FIGS. 20-22), such that thedesired compression of the plate 110 against the bone 14 is provided,and then the partially seated set screw 176 is fully driven down againstthe hinge clamp 178 to cause the hinge clamp to impinge on the cable 26and secure the cable at the desired tension.

Turning now to FIG. 9, a compression plate 210 is shown with anotherintegrated cerclage cable securing structure. The plate 210 has twotransverse cable passages 266, 268 extending through the width of theplate 210. The first transverse passage 266 allows passage of the freeend 26 b but restricts passage of the stop end 26 a of the cable 26. Thesecond transverse passage 268 also allows passage of the free end 26 btherethrough. A slot 270 is provided within the plate extending throughthe second passage 268 but preferably terminating short of the firstpassage 266. At a first end of the slot 270, the slot extends up to theupper surface 272 of the plate. The plate material is reduced at theupper surface over the second end of the slot 270 to define a dynamichinge that is elastically deformable; i.e., to result in a hinge clamp278. According to one such structure, a transverse groove 280 is formedin the upper surface of the plate, thus defining a dynamic hinge for ahinge clamp. Alternatively, as shown in FIG. 10, the material thicknessmay be reduced below the plate surface, e.g., with an enlargedtransverse hole 280′, to define the elastically deformable hinge clamp278′. Referring to both FIGS. 9 and 10, between the first and secondends of the hinged clamp 278, 278′, a set screw hole 274, 274′ isdefined within the hinge clamp and plate portion therebeneath, with theportion therebeneath being threaded. A set screw 276 is partiallythreaded in the set screw hole. As the set screw 276 is advanced, thehinge clamp 278, 278 impinges on the space of the second passage 268,268′.

Referring generally to FIG. 9, in use, the cable 26 is first fed throughthe first passage 266 until the ball end 26 a of the cable is retainedat the opening thereof. The free end 26 b of the cable is then circledabout the bone (not shown), and inserted into and through the secondpassage 268. The cable 26 is drawn into tension, preferably using theinstrument 710 described below (FIGS. 20-22), such that a desiredcompressive force between the plate and bone is obtained, and then thepartially seated set screw 276 is fully driven down to cause the hingeclamp 278 to reduce the transverse dimension of the second passage andthereby impinge on the portion of the cable 26 within the second passage268 such that the cable is secured at the desired tension. The flexinglimits of the hinge portion of the hinged clamp (i.e., that portionunder the transverse groove 280 (FIG. 9) or above the enlargedtransverse hole 280′ (FIG. 10)) remains within the elastic limits of theplate material and does not undergo plastic deformation when the setscrew 276 is fully driven down to secure the cable.

Turning now to FIGS. 23 through 26, a compression plate 810,substantially similar to plate 210 (with like reference incremented by600 corresponding to similar structure), is shown with the same orsubstantially similar integrated cerclage cable securing structure asshown with respect to the plate 210. The plate 810 defines first andsecond transverse cable passages 866, 868 extending through the width ofthe plate. The first transverse passage 866 extends under the hingeclamp 878 as described above. The second passage 868 is a steppeddiameter bore extending through the plate at a longitudinally displacedlocation from the hinge clamp 878. The cerclage cable 826 includes aball end 826 a, and a compression coil spring 879 is provided about theend of the cable and in abutting contact with the ball end 826 a.Alternatively, the spring may be different type of spring, such as aleaf spring or a Belleville washer, and additionally the spring may beinstalled in the second passage before the insertion of cable 826therethrough. When the cable 826 is advanced through the second passage868, the ball end 826 a and spring 879 are retained in a larger diameterportion 868 a of the passage 868, and the cable 826 continues through asmaller diameter portion 868 b of the plate. The cable is then circledabout the bone (not shown), and inserted into and through the secondpassage 866 and drawn into tension, resulting in compression of thespring 879, preferably using the instrument 710, 710′ described below(FIGS. 20-22, 29-30), preferably until a desired compressive forcebetween the plate and bone with spring compression is obtained. That is,the spring 879 is adapted to compress in proportion to the tensionapplied to the cable 826. Then, a crimp 886 is applied to the free end826 b of the cable adjacent the side of plate 810 to secure the tensionon the cable. Alternatively or additionally, the free end may be securedwith a dynamic hinge clamp integrated with the plate as described aboveand as shown in FIGS. 5 through 10. Once the tension is secured, theremaining cable beyond the plate and/or crimp 886 may be cut free. Thespring 879 on the cable provides a degree of elasticity to the fixationthat is not otherwise present in the assembly of the plate to the bone.Thus, in the event of micromotion, minor movement, or even slippage ofthe cable 826 on the bone or relative to the plate, the construct willcontinue to maintain tension to support the bone throughout the healingprocess.

Turning now to FIGS. 11 and 12, a compression plate 310, substantiallysimilar to plate 210, is shown with another integrated cerclage cablesecuring structure. The plate includes a lower surface 324, an uppersurface 372, sides 325 a, 325 b extending between the upper and lowersurfaces, a length along said sides defining longitudinal axis A₂, aheight extending between the upper and lower surface, and a widthtransverse to the length and the height. The plate 310 defines first andsecond transverse cable passages 366, 368 extending through the width ofthe plate. The first transverse passage 366 includes outer portions 366a, 366 b that allow passage of both the free and stop ends of the cable,and an interposing centrally displaced cantilevered deflection beam 382(preferably extending along the longitudinal axis A₂) that restrictspassage of the stop end 26 a of the cable. The deflection beam 382 isadapted to deflect in proportion to the tension applied to the cable 26.In addition, the deflection beam 382 is preferably paired with indicia384 on the beam and/or the plate such that the beam 382 and indicia 384together indicate at least a relative amount of tension applied to thecable 26 as the beam 382 is displaced or flexed through applied tension.The beam 382 and indicia 384 are preferably visible under fluoroscopy sothat the relative cable tension can be ascertained during the surgicalprocedure, and even after the surgical wound has been closed and at anytime post-operatively.

In use, the cable 26 is advanced through the first passage 366 until thestop 26 a engages the deflection beam 382. The free end 26 b of thecable is then circled about the bone (not shown), and inserted into andthrough the second passage 368. The cable is drawn into tension,preferably using the instrument 710 described below (FIGS. 20-22), untila desired compressive force between the plate and bone is obtained.Then, a crimp 386 is applied to the free end 26 b of the cable adjacentthe side of plate 310 to secure the tension on the cable. Alternatively,the plate may additionally be provided with an integrated hinged clamp,as described above, or other integrated securing element for securingthe free end of the cable, such that, e.g., a set screw can be advancedto impinge on the cable and secure the cable at the desired tension.Once the tension is secured, the remaining cable beyond the crimp 386may be cut free.

With the integrated deflection beam 382, the surgeon is able to visuallydetermined the tension force on the cable by inspecting the amount ofdeflection imparted to the beam 382, and can adjust the tensionaccordingly. This is, of course, enabled without increasing the heightprofile of the plate 310 (between lower and lower surfaces 324, 372) orcable 26. In addition, the cable 26 is provided with a degree ofelasticity that it is not inherently part of its construction. Thus, inthe event of micromotion or minor slippage of the cable 26 on the boneor relative to the plate, the construct will continue to maintaintension to support the bone throughout the healing process.

Referring now to FIGS. 13 through 17, in accord with another aspect ofthe invention, the system includes discrete crimp lugs 510 for use witha compression plate 410. The plate 410 shown is a midshaft plate, butthe following is applicable to any plate suitable for use inperiprosthetic fracture fixation. The crimp lugs 510 are provided forguiding and securing the ends of a cable relative to each other intension about the plate 410 and bone 14. The plate 410 preferablyincludes a plurality of a longitudinally displaced threaded holes 412and one or more longitudinal compression screw slots 414. In alignmentwith each of the threaded holes and slots 412, 414 are transversegrooves 416 adapted in size (depth and diameter) for stabilized guidanceof a cable in a direction transverse to a longitudinal axis A₃ of theplate 410 and bone 14.

Each crimp lug 510 includes a head 512 and a retaining feature 514 thatpermits the positioning of the crimp lug within a screw hole 412, 414 ofthe plate. Most preferably, the crimp lugs are attached relative to thethreaded screw holes 412 and thus the retaining feature is adapted forengagement therein; however, the crimp lugs can be adapted forattachment at non-threaded round screw holes or non-circular screwslots.

The head 512 includes two eyelets 516 extending through a wall thicknessof the lug, wherein the wall thickness extends in a dimension parallelto the transverse grooves 416 when a lug 510 is attached to the plate410. The eyelets 516 are preferably sized to retain a stop 26 a at theend of the cable 26 but to permit feeding the free end 26 b of the cabletherethrough. While the crimp lug 510 is preferably made as a unitarypiece from a single material, it can be a composite structure. At leastthe head 512 is made from titanium or cobalt chrome or another materialthat can be collapsed on a cable 26 within the eyelets 516 withsufficient force to prevent cable pullout therefrom.

Referring to FIGS. 14 through 16, in one embodiment, the retainingfeature 514 includes a pair of legs 518, each having a reduced upperthickness portion 520 about which they can resiliently articulate,resiliently bend, or otherwise resiliently deform. The lower end of eachof the legs includes an outwardly extending foot portion 522 that isadapted to capture the plate at underside of a screw hole. Otherpossible retaining features for the at least temporary coupling thecrimp lugs to the plate include: corresponding shapes between theretaining structure and the holes, corresponding dimensions adapted forfrictional interference with the threaded or slot holes, non-resilient,plastically deformable structure insertable into the holes, externalthreads for threading with the threaded holes, or other structurepermitting mechanical interference between the lug and the plate at thescrew hole.

In use, an independent and discrete crimp lug 510 is positioned within ascrew hole 414. In view of the mechanical interference between the crimplug 510 and plate 410, the crimp lug 510 is coupled to the plate 410 asthe surgeon handles the plate, regardless of the orientation of theplate, and further while the surgeon subsequently feeds cable 26 throughthe eyelets 516 of the crimp lug 510. The cable 26 is placed undertension and the lug is then plastically deformed about the cable (asshown in FIG. 17) to retain the tension, e.g., with a pliers. Then theremaining cable is cut and removed.

There may be instances in which it is desirable to guide and secure acerclage cable about a bone independent of a bone plate. Turning now toFIGS. 18 and 19, in accord with yet another aspect of the invention, thesystem includes independent and discrete crimp lugs 610, and 610′,provided with retaining features for attachment of the respective lugsrelative to the bone independent of a plate. Crimp lug 610 (FIG. 18)includes a plastically deformable preferably trapezoidal head 612 withtwo eyelets 616 extending through a wall thickness of the lug, asdescribed with respect to crimp lug 510. While the preferred shape ofthe head 612 is trapezoidal, as such accommodates the eyelets in a lowprofile on the bone or in the plate and is readily deformable to retainthe cable, it is appreciated that the retainer can be provided with ahead of another shape. The retaining feature is a barbed tack 614. Crimplug 610′ (FIG. 19) includes a substantially similar head 612′ providedwith a retaining feature of a sharpened smooth nail end 614′, alsopermitting the lug to be driven into the bone for temporary or permanentfixation. In each of the embodiments of FIGS. 18 and 19, the heads612/612′ of the lugs 610/610′ may have increased rigidity in axialdirection (parallel to the extension of the post) such that it can bedriven into the bone without significant deformation of the eyes616/616′, and then only after the cable has been advanced through theeyes and placed under the tension, the lug is deformed by plasticdeformation of the head, preferably via application of a deformationforce in a widthwise direction to the lug. As yet another alternative,the retaining feature may include a threaded shaft with preferablyself-tapping threads adapted for insertion into bone.

Referring to FIGS. 27 and 28, a tool 900 is provided for handling andinserting independent and discrete crimp lugs. The tool 900 includes atubular housing 902 and a shaft 904 insertable within the housing. Thehousing 902 defines a central bore 906 having a thread 908 at itsproximal end and opening 910 at a distal end to a lug receiver 912. Thereceiver 912 is defined by two arms 914 a, 914 b together with an endface 916 defining a trapezoidal opening sized to closely accommodate thetrapezoidal head 612 of the lug 610, with the barbed tack 614 of the lug610 extending distally from and beyond the receiver. It is appreciatedthat if the head of the lug is provided with another shape, the receiveris likewise designed to accommodate it in shape to closely receive it.The housing also preferably include external grooves 918 to facilitatesecure manipulation. The shaft 904 includes a proximal end provided withknurled knob 920 having a preferably flat proximal end 922, threads 924adjacent the knob, and a distal end 926. The shaft 904 is inserted intothe bore 906 of the housing 902 and retained relative to the housing viaengagement of the threads 924, 908. The housing 902 and shaft 904 canhave a threaded engagement at alternative locations, such as about theexterior of the housing, or at or near the distal end of the tool.

In use, the knob 920 is rotated relative to the housing 902 to positionthe distal end 926 of the shaft in a retracted position relative to thedistal opening 910. A crimp lug 610 is positioned in the receiver 912,and then the knob 920 is rotated to advance the distal tip in contactwith the head 612 of the crimp lug 610 and secure it into the receiver912. The lug 610 may then be easily manipulated by the tool 900. Inaddition, once the lug is maneuvered to the intended implant location,the proximal knob 920 of the tool may be struck with an impactor, suchas a smaller hammer, to drive the lug 610 securely into bone. Then theknob 920 is rotated relative to the housing 902 to withdraw the distaltip 926 from contact against the head 612 of the lug 610 and release thelug from the tool 900.

Turning now to FIG. 20 through 22, the system is also preferablyprovided with a cable tensioner 710. The cable tensioner 710 may be usedto tension a cerclage cable advanced through the passages of anintegrated cable securing structure on a plate, or through the eyeletsof a separate crimp lug, or a simple crimp, each as described above, orin association with any plate or other cable securing component, whetheror not having the foregoing features, but preferably having a passagethrough which a cable may be passed.

The cable tensioner 710 is a single device having a distal cerclagecable guide tube 712 leading to and connected to a proximal gear boxhousing 714. The tube 712 has a distal end 716 pre-formed with a gentlecurve to facilitate the approach to a compression plate or cable lug 718from outside a surgical wound. This provides the surgeon with additionalspace and clearance to work and displaces the working mechanism of thegearbox 714 away from the plate or crimp to retain visibility at thesurgical site and working clearance. The proximal end 720 of the tube712 is removably secured to the gearbox housing 714 with a lockpin 724that engages a proximal lip 722 of the tube.

The gear box housing 714 includes worm screw 726 having a torque driversocket 728. The worm screw 726 is in gear-engagement to a drive gear 730which is rotationally fixed to a cable pulley 732. A threaded tubularshaft 734 extends from the cable pulley 732 through a shaft mount 736 ofthe gear box housing 714. A collet 738 extends over the shaft 734. Alocking knob 740 with a central opening 742 extends over the collet, andis threadedly mounted to the shaft 734 of the pulley 732. The tubularshaft 734, collet 738 and opening 742 define a cable passage extendingtransverse to the rotational axis of the worm screw 726. Rotation of theknob 740 in one direction decreases resistance to rotation of the pulley732, whereas rotation of the knob in the opposite direction functions toincrease resistance on pulley rotation relative to the housing 714. Thepulley 732 has a plurality of grooves 744 opening in the sidewall of thetrack 745 of the pulley, and a guide bolt 746 or other guide structurelocated at each groove, the functions of each being described below.

In operation, after the free end of a cable 26 b is advanced through aplate passage, lug 718, crimp, or other structure, with the stop end 26a of the cable retained in place, the free end 26 b of the cable is thenpulled and the distal end 716 of the tube of the cable tensioner isadvanced towards the plate or crimp lug 718 until the tube 712 contactsor approximates the plate or crimp lug. The cable 26 may be threadedthrough the tube 712 with the tube separated from the gearbox housing714, by removal of the lockpin 724. After the cable 26 has been advancedthrough the tube 712, the free end 26 b is passed around the track 745of the pulley 732 and through one groove 744 of the pulley 732(generally the groove nearest the proximal end of the gear box, orfurthest from the distal end of the tube), about the adjacent guide bolt746, and through the cable passage defined by the tubular shaft 734, thecollet 738, and the opening 742 in the locking knob 740. The pulleygrooves 744 are preferably angled openings that will grab the cable 26as the pulley 732 is rotated. The guide bolts 746 ensure a smoothtransition by the cable 26 from the pulley 732 to a transverseorientation through the cable passage, without crimping or misfeed ofthe cable. If the tube 712 and housing 714 were previously disassembled(by removable of the lockpin 724), they are reassembled by inserting thelip 722 at the proximal end of the tube into the housing andre-inserting the lockpin 724 to engage the lip 722 and thereby preventtube separation.

The cable 26 is then manually pulled until there is no cable slackbetween the tube 712 and the pulley 732. Then the locking knob 740 isrotated until a relatively taught cable 26 is secured in the proximalhousing 714 of the tensioner 710, all without the need for a separatepretension clamp to hold tension on the cable. A driver (not shown) isnext engaged in the socket end 728 of the worm screw 726. As the driveris rotated in a first direction the worm screw 726 rotates to “spool”the cable 26 about the pulley 732. The portion of the cable extendingaround the plate and bone decreases and compresses the plate onto thebone. Also, if the driver is rotated in an opposite second direction,the length of cable extending about the bone is increased, the tensionon the cable is decreased, and the applied compression between the plateand bone is decreased. Rotationally driving the screw 726 providessuperior tactile feedback over using a rotation knob or a pistol gripfor applying tension on the cable and compression between the plate andbone. Once the desired compression is applied between the plate andbone, the integrated cable securing structure, crimp lug 718 or otherstructure is secured onto the cable 26 to retain the applied tension onthe cable.

Turning now to FIGS. 29 and 30, another embodiment of a cable tensioner710′, substantially similar to tensioner 710, is shown. The cabletensioner 710′ has a guide tube 712′ leading to and connected to aproximal gear box housing 714′. In distinction from the tensioner 710,the tensioner 710′ includes several additional features that couldsimilarly be incorporated into tensioner 710 or another tensioner. Withadditional reference to FIG. 30A, between the tube 712′ and the housing714′, the tensioner 710′ includes a compression spring 750′, a tensiongauge 752′, and a cable tension lock 754′. The compression spring 750′is preferably a Belleville washer spring extending in outwardcompression. The gauge 752′ includes a collar 753′ having a shoulder755′ at the proximal end of the guide tube 712′ that sits in contactwith the distal end of the compression spring 750′. The gauge alsoincludes a pin 756′ that rides in a longitudinal slot 758′ within alocking housing 760′. As tension is applied to the cable 26 by thegearbox in housing 714′, the shoulder 755′ is loaded against the spring750′ to compress the spring and thereby displace the pin 756′ of thetension gauge 752′ within the slot 758′. The pin 756′ is displaced inproportion to the amount of force applied. Indicia 762′ are providedalong the side of the slot 758′ to indicate the applied tension orrelative tension. The cable tension lock 754′ includes a cam arm 764′that rotates to move a cam 765′ between a first position in which thecable can be longitudinally displaced relative to the tube 712′, and asecond position in which the internal cam 765′ compresses against thecable 26 to lock its longitudinal position relative to the tube 712′ (asshown in FIG. 30A). Other suitable locking mechanisms to temporarily fixthe position of the cable and the tension thereon while the cabletensioner is in use can also be used.

According to another aspect of the invention, the gear box housing 714′can be disengaged and removed proximal to the cable tension lock 754′,so that once the cable is tensioned and the lock is used to retain thetension, the housing can be removed to operate with another cable andtube and the tension on the cable is maintained. The housing can beremoved from the relatively distal assembly by releasing lockpin 724′(see like component 724 in FIG. 21) or another retaining fastener whichengages a grooved neck 753′ at the proximal end of the tension lock 754′(FIG. 30A). As such, fewer components are required and costs can bereduced. More particularly, FIG. 29A illustrates a single gear boxhousing 714′ being used sequentially with three tubes 712′a, 712 b,712′c, and cables 26 a, 26 b, 26 c for preliminary application andmaintenance of tension to the respective cables in advance ofpermanently fixing the tension on the cable with an appropriate plate110 and/or lugs.

Turning back to FIG. 29, the gearbox housing 714′ of the cable tensioner710′ is also provided with a pulley 732′ and a locking knob 740′,coupled to the gear box housing 714′, each of a slightly differentdesign than the respective counterparts in tensioner 710. Pulley 732′has a bulbous outer surface extending from the track 745′ of the pulley,and three grooves 744′ extending from the track over the bulbous surfaceinto the cable passage (described above with respect to tensioner 710).Such design facilitates smooth guidance of the cable. The locking knob740′ is relatively larger than knob 740 and includes three large grips741′ (two shown) to facilitate handling and rotation of the knob 740′.The remaining components are substantially as described with respect tothe gearbox of tensioner 710.

The cable tensioner 710, 710′ is a single, small size, light weightinstrument that can temporarily hold tension as well as increase tensionto apply final securing tension. In addition, the device includesrelatively few components and can be manufactured as either a reusableinstrument, or as a one-time disposable instrument. The ease of useprovides increased surgical efficacy and reduces the procedure time.Further, the device is relatively intuitive to use and can be learnedwithout a significant learning curve.

It is recognized that certain periarticular fractures may notnecessitate the use of a cerclage cable and the associated open surgicalprocedure necessary to implant such cable about the plate and the bone.If the option to avoid open surgery is available, it is often preferred,as trauma to the patient is reduced and recovery times can besignificantly decreased. Various plates, such as mid-shaft plate 410described above in association with FIG. 13 and a metaphyseal plate 1010(1010 a) described below in association FIGS. 31-39, are well-adaptedfor a minimally invasive ‘closed’ surgical approach in conjunction witha jig system, such as the jig system described below with respect toFIGS. 40-49.

Turning now to FIGS. 31 and 32, a distal femoral plate 1010 is shown.The plate 1010 has a longitudinally extending shaft portion 1011 with atapered proximal end 1012 to facilitate entry into a small incision andbetween the soft tissue and the bone. The distal end 1014 is shaped toaccommodate the metaphysis of the distal femur. Alternatively, thedistal end 1014 of the plate may include other structure than shown forplacement against the metaphysis.

The plate 1010 includes screw holes 1016, 1018 at which bone screws canbe selectively received, and optionally transverse grooves 1020 areprovided adjacent such screw holes for the stabilized guidance of acable (not shown) in the event the plate is utilized in an openprocedure, to which the plate is also adapted. Grooves 1020 aredescribed further with respect to FIG. 13. The screw holes includethreaded holes 1016 that secure fixed angle bone screws (not shown) tothe plate. Such fixed angle bone screw are known in the art and have ahead with external threads that mate with the threaded holes to retainthe screw directly to the plate 1010 and in alignment with a centralaxis of the threaded hole. Further, such fixed angle bone screws areadapted to not generate significant compressive force between the screwand plate as the screw is advanced into the bone and secured to theplate. The screw holes also include elongate, preferably non-threadedcompression holes 1018, each for receiving a compression fastener 1024(FIGS. 33-36) that utilizes the head 1026 of the screw to compress thebone plate 1010 against the bone 1030 as the threaded shaft 1028 of thescrew is advanced into the bone. The head 1026 preferably has a convexlower surface 1032, which may alternatively be conical in design.

In accord with one aspect to the invention, the elongate compressionholes 1018 are dynamic compression holes constructed to allow higherdynamic compression to be applied across a fracture beneath the platethan known compression holes permit. In general, dynamic compressionholes are holes that are adapted to interact with a compression screwhead to generate a longitudinal force on the screw, and thus against thebone into which the screw is driven. The force is a radial componentgenerated by the shape of the screw head against one end of thecompression slot. As the screw is axially driven, the underside of thehead of the screw interferes with an end of the slot. As a result of thecurvature (or angle) at the underside of its head, the screw head pushesradially outward from the end of the slot to result in displacement ofthe bone beneath the plate in a manner that effects compression acrossthe fracture. In the prior art, as represented for example by U.S. Pat.No. 3,552,389 to Allgower et al., the amount of compression isconstrained by the geometry of the screw. As a screw is driven, the bonedisplacement is limited to ½ (diameter of the screw head—major diameterof the screw shaft), which represents the radial overhang of a screwhead beyond the screw shaft. In the dynamic compression holes 1018 ofplate 1010, the displacement of the screw and the compression across thefracture is generated by the plate geometry and not necessarily thescrew geometry. As a result, the magnitude of movement of the bonebeneath the plate is not limited by the geometric constraints of theprior art.

More particularly, referring to FIGS. 31-33 and 37, the compression hole1018 is an elongate hole that includes a screw ramp 1040 extending froma first end 1042 of the hole toward a second end 1044 of the hole, and alongitudinally flared recess 1046 adjacent the second end 1044 of thehole at the upper surface 1047 of the plate. In accord with anotheraspect of the invention, discussed below, the hole 1018 also includes alongitudinally flared lower recess 1048 beneath the first end 1042 ofthe hole, flaring in a direction opposite the upper recess 1046.

In reference to when a lower bone contacting surface 1048 of the shaftof the plate 1010 extends along a substantially horizontal plane P (FIG.33), the screw ramp 1040 has a downward slope, preferably at a constantangle, and has a length that extends preferably more than half thelength of the screw hole 1018 and more specifically has a lengthsufficient to cause a screw head 1026 traveling down the ramp to contactthe recess 1046 at the second end 1044 (i.e., far side) of the screwhole once the screw head has traversed to the bottom of the ramp, asshown through FIGS. 33-38. Referring to FIGS. 31, 33 and 37, the screwramp 1040 includes an upper bevel surface 1050 against which the lowersurface 1032 of the head 1026 of the screw contacts, and a side wall1052 defining opposing sides 1054, 1056 with opposing points of contactwhich stabilize the shaft 1028 of the screw. In one embodiment, theopposing sides 1054, 1056 are straight and preferably vertical sidewalls. Alternatively, the opposing sides 1054, 1056 can have convexsurfaces providing sufficient point contact relative to the shaft 1028of the screw 1024 to stabilize the advancement of the screw through thehole.

In operation, a first portion of the plate 1010 is longitudinally fixedto a bone with a first bone fastener on a first side of a fractureacross which compression is required. Then, on an opposite side of thefracture, a screw 1024 is positioned with its shaft 1028 insertedadjacent the first end 1042 of the hole 1018. The screw 1024 is advancedinto the bone until the lower surface 1032 of the screw head 1026contacts the bevel surface 1050 at the first end 1042 (FIG. 33). Turningto FIGS. 34 and 37, as the screw 1024 is further advanced to providecompression against the plate 1010, the lower surface 1032 of the screwhead will radially push off from the first end 1042, and the screw willseek to ride down the ramp 1040 to the lowest elevation within the screwhole. As the screw cannot longitudinally move within the hole as its isaxially driven—the shaft is longitudinally fixed within the bone1030—both the plate 1010 and the bone fixed to the plate at the firstbone fastener move relative to the screw 1024. The screw is furtheradvanced, as shown in FIGS. 34 through 36 and 38, drawing the fractureinto compression until the screw head seats at the bottom of the ramp1040 and in contact with the second end 1044 of the screw hole. Theupper recess 1046 is adapted to accommodate the full size of the screwhead 1026 so that the screw head seats flush or substantially flush withthe upper surface 1056 of the shaft of the plate. Given the geometry ofthe screw hole, the potential displacement is limited only by the lengthof the ramp 1040. More specifically, it is anticipated that thecompressive displacement will always be greater than the radial overhangof the screw head beyond the screw shaft, and more preferably at leasttwice the radial overhang, potential many multiples of the radialoverhang. FIG. 36, by way of example only, illustrates a compressivedisplacement of approximately four times the radial overhang of thescrew head beyond the screw shaft.

The direction of the compression hole is preferably perpendicular to thefracture line to provide maximum displacement of the plate relative tothe fracture. The compression hole 1018 is shown extending parallel, andmore specifically on axis with, the center line CL of the diaphysealportion of the plate in FIG. 31. This arrangement accommodates theuncertainty of the location of the fracture line as well as a desirableaesthetic for the plate. As an alternative, referring to FIG. 39, plate1010 a is shown with the long axis of a compression hole 1018 aobliquely oriented relative to the centerline of the plate toaccommodate the curvature of the diaphysis of the bone and/or fracturelocations and directionality shown to have an historical tendency tooccur. By way of example only, the oblique orientation of the long axismay be at an angle between 0°-30° relative to the center line CL. Suchhole orientation permits maximum compressive force to be appliedperpendicular to a fracture line that is also oblique relative to thecenterline of the plate. Further, plate 1010 a illustrates that multiplecompression holes 1018 a can be provided along the shaft of the plate toprovide options in the location at which compression is applied. Forgreatest mechanical advantage, it is most preferable to applycompression at the compression hole 1018 a located closest to thefracture line; however given the uncertainty of the location of thefracture line, the plurality of compression holes along the shaftportion of the plate provides several options for most beneficialplacement of the compression screw. Moreover, multiple dynamiccompression holes in the same plate can have their axes obliquely and/oraxially relative to the center line and extending at different sidesrelative to the center line to provide a best case approach for maximumcompressive force perpendicular to a fracture line, particularly giventhe unpredictability of the fracture line.

Turning now to FIG. 40, jig 1100 is shown coupled to the plate 1010 a ina manner that facilitates minimally invasive insertion of the platethrough an incision, and deploying screws from outside the patient,through the soft tissue surrounding the bone, and into the plate tosecure the plate to the bone. The jig 1100 includes a jig arm 1102 thatcouples relative to the plate 1010 a via a jig base 1104. The jig arm1102 includes a plurality of jig holes 1110 having the samecenter-to-center spacing as the screw holes 1016 of the bone plate, andbeing configured to orient components inserted therethrough over thescrew holes 1016, 1018 a of the plate, as described below. All of thejig holes 1110, with the exception of the one jig hole 1110 a locatednearest a first end 1111 of the jig arm, are threaded. The jig arm 1102may be straight or curved as necessary to extend over the plate 1010 a,and is preferably designed with a sufficient number of jig holes 1110 toseparately accommodate plates of various lengths, provided such variouslength plates each have holes that are arranged along a commonlongitudinal axis, extend in common axial orientation, and have a commoninter-hole spacing. Alternatively, separate jig arms may be provided forplates of individual sizes and curvatures. The first end 1111 of the jigarm includes a first side 1112 with a reduced stepped width firstportion 1114, and a second side 1116 with a stepped reduced width secondportion 1118. The jig holes 1110 extend between the first and secondsides 1112, 1116. The jig base 1104 includes first and second ends 1120,1122, each provided with a respective recess 1124, 1126, and athroughbore 1128 extending in communication between the first and secondrecesses 1124, 1126.

In assembling the jig 1100 to the plate 1010 a, the jig base 1104 ispositioned over a threaded screw hole 1016 on the plate, with the base1104 straddling the upper surface 1032 of the plate 1010 a at the secondrecess 1126. The jig arm 1102 is adapted such that either of the reducedwidth first or second portions 1114, 1118 can be received in the upwardoriented first recess 1124. The orientation of the jig arm 1102 isgenerally dependent on whether the plate is adapted for a left or rightside bone of the patient and the adaptive contours of such plate; thejig arm 1102 is always oriented within the first recess 1124 to followany curvature of the underlying plate 1010 a.

A locking guide 1130 is then inserted through the jig hole 1110 a at thefirst end 1111 of the arm, through the throughbore 1128, and into anunderlying threaded screw hole 1016 of the plate 1010 a. Referring toFIG. 42, the locking guide has a longitudinal bore 1150. The distal endof the locking guide 1130 has a tapered threaded portion 1132 and issplit at two orthogonally oriented compression slots 1140, 1142extending longitudinally into the distal end of the guide 1130. Thetapered threaded portion 1132 is adapted to threadedly engage threadedscrew holes 1016. The tapered and split construction allows the guide tobe rapidly advanced into the screw holes 1016, yet allows significantradial loads to be developed at the threads as the tapered threadedportion 1132 is advanced into a threaded hole 1016 to provide a secureengagement at the plate 1010 a. Turning back to FIG. 40, a proximal end1134 of the locking guide preferably includes an axial driver recess1136, such as a hex opening to drive the guide 1130 relative to the jig1100 and plate 1010 a. In addition or alternatively, radialthrough-holes 1138 in which to receive a lever to apply torque to thelocking guide are radially displaced, preferably at 90° apart, about theproximal end of the locking guide. Such through-holes 1138 can belocated on a larger diameter collar 1140 fixed at the proximal end ofthe guide to provide increased mechanical advantage. In addition oralternatively, external flats, such as in the form of a hex, can beformed on the outer proximal end of the locking guide, including thecollar 1140, to facilitate engagement by a tool to apply torque.

Once the jig 1100 is rigidly assembled relative to the plate 1010 a, thejig can be used as a handle to manipulate the plate, and advance thetapered end 1012 of the plate through a small incision until the platelies in an intended position between long bone and the overlying softtissue. By way of example, the long bone is the femur and the softtissue is muscle, facia, and skin surrounding the femur. The plate isthen fixed relative to the bone with screws. If the plate includes aportion having bone screw holes which are exposed at the incision suchas metaphyseal portion 1014 of the plate 1010 a, such portion ispreferably first coupled to the bone to provide initial plate fixation.

Then, each bone screw used for securing the plate at portions remainingunexposed beneath the soft tissue is advance through the soft tissue andto the plate preferably in accord with the following method, generallyillustrated in FIG. 41. However, it is noted that FIG. 41 illustratesvarious stages of the methodology, which would not necessarily beoccurring at the same time during a surgical procedure. As such, FIG. 41should be considered as illustrative only and should be considered incontext of the following preferred order for steps for the procedure.

Referring to the right side of FIG. 41, a trocar 1300 is slidablydisposed within an outer sleeve 1200, and the two are together advancedthrough the soft tissue down to the plate 1010 a. The outer sleeve 1200has a proximal collar 1202 and a sleeve 1204 with a length adapted toextend from the first side 1112 of the jig arm to the upper surface 1032of the plate 1010 a. As shown in FIG. 43, a proximal end 1206 of thesleeve is provided with external threads 1208 adapted to threadedlyengage the jig holes 1110 to fixedly couple the outer sleeve 1200relative to the jig 1100, and consequently the plate 1010 a. The trocar1300 has a proximal collar 1302 adapted to rest on the collar 1202 ofthe outer sleeve 1200, and a pointed distal end 1304 adapted topenetrate and separate the soft tissue as the two are advanced. Thetrocar 1300 has a length such that once the sleeve 1200 is fixedlycoupled to the jig arm 1102, the trocar 1300 can extend completelythrough the soft tissue, through the respective screw hole, and providean initial pilot marking on bone when the collars 1202, 1302 are in anabutting relationship. The trocar 1300 is then removed, while the outersleeve 1200 remains fixed in place.

Referring to the left side of FIG. 41, an outer sleeve 1200, advancedwith a trocar 1300 as described above, is shown in place adjacent thelocking guide 1130. After the trocar 1300 is removed, a drill guide 1400is advanced through the outer sleeve 1200. As shown in FIGS. 41, 44 and45, the drill guide 1400 includes a proximal collar 1402 and a tubularmember 1404 with a longitudinal bore 1406. The collar 1402 is sized tostably seat on the collar 1202 of the outer sleeve 1200 and functions asa manual handle for manipulating the guide 1400. Optionally, an axialdriver recess 1408 for coupling a torque driver to the collar 1402 isprovided its proximal end. It is appreciated that the collar 1402 issized to be used as a handle for manual rotation as well. In accord withone aspect of the invention, the tubular member 1404 has a distal end1410 provided with hole engagement structure 1412 adapted to couple witheither a threaded hole 1016 or a non-threaded slot 1018 a in the boneplate 1010 a. Turning now to FIGS. 46 and 47, the hole engagementstructure 1412 includes a tapered threaded portion 1414 threadedlyengagable with the threaded screw hole 1016. A neck portion 1424 isprovided proximally to the threaded portion 1414. The neck portion 1424has a reduced diameter relative to the threaded portion 1414, a maximumdiameter Dn greater than the width of the screw hole slot 1018 a, and alength Ln exceeding the thickness of the sides 1054, 1056 of the screwhole slot 1018 a (FIG. 48). A lip 1426 is defined at the upper end ofthe threaded portion 1414, and a shoulder 1428 is defined at theproximal end of the neck portion. The hole engagement structure 1412also includes opposing flats 1420, 1422 extending longitudinally throughthe threaded portion 1414, the lip 1426, and the neck portion 1424. Theflats 1420, 1422 are displaced apart from each other by a distance Dfwhich is less than the width of the screw hole slot 1018 a at the sides1036, 1038. A compression slot 1416 extends diametrically andlongitudinally through an entirety of the flats 1420, 1422, and furtherin a direction transverse to the maximum diameter Dn of the neckportion. While the diameter Dn is greater than the width of the screwhole, it does not exceed the width of the screw hole slot 1018 a, asdefined as the dimension between the sides 1036, 1038, by more than thewidth Ws of the compression slot 1416.

Where the drill guide 1400 is advanced through the outer sleeve 1200 andinto position over a threaded screw hole 1016 of the plate 1010 a (asshown with respect to the position of the left outer sleeve 1200 in FIG.41), the drill guide is threadedly engaged with the threaded screw holeat the threaded portion 1414. A torque driver (not shown) may be coupledto the drill guide 1400 at the recess 1408 to apply sufficient torque tothe drill guide in order to secure the assembly of the guide 1400 to theplate 1010 a. As the torque is increased, the distal end of the guidemay compress across the compression slot 1416 increasing the resistanceto unintended pullout. Once the drill guide 1400 is securely engaged tothe plate, a drill bit is advanced through the drill guide and operatedto drill a hole for the shaft of the bone screw at the location beneaththe bone plate. The drill is removed, and then the drill guide 1400 isremoved. A fixed angle screw is advanced through the outer sleeve 1200and driven into the bone and plate 1010 a with a torque driver. Theouter sleeve 1200 is then removed from engagement with the jig 1100.

Referring to FIGS. 48 and 49, where the drill guide 1400 is advancedthrough the outer sleeve 1200 and into position over a non-threadedelongate dynamic compression slot 1018 a (as shown with respect to theposition of the right outer sleeve 1200 in FIG. 41; i.e., with the drillguide replacing the position of the trocar 1300 shown in FIG. 41), thedrill guide is rotated such that the flats 1420, 1422 are parallel tothe elongate sides 1054, 1056 of the slot 1018 a. In this orientation,the threads 1414 are passed through the screw slot 1018 a, withoutthreaded engagement thereof, and until the neck portion 1424 resideswithin the screw slot. The drill guide 1400 is then rotated one quarterturn; i.e., by 90°, in either rotational direction about itslongitudinal axis. As the diameter Dn of the neck portion 1424 isgreater than the width of the screw hole slot 1018 a, but not by morethan the width Ws of the compression slot 1416, the neck portion 1424radially compresses like a spring about the compression slot 1416. (SeeFIGS. 46-47 regarding the referenced dimensions.) This results in thehole engagement structure 1412 capturing the plate at the compressedneck portion 1424 and between the lip 1426 and the shoulder 1428,thereby locking the dill guide 1400 relative to the hole 1018 a. Thelower recess 1048 surrounding the first end 1042 of the compressionscrew hole 1018 a (shown in FIG. 32) provides clearance for rotation ofthe lip 1426 into the locking position. The surgeon receives tactilefeedback as the compression increases, and is thus provided feedback asto the secured relationship of the guide 1400 relative to the plate 1010a.

Once the drill guide 1400 is securely engaged to the plate, a drill bitis advanced through the drill guide and operated to a drill hole for theshaft of the bone screw at the location beneath the bone plate. Thedrill is removed, and then the drill guide is removed. A compressionscrew is advanced through the outer sleeve 1200 and driven into the boneand plate 1010 a with a torque driver. It may be necessary to loosen theouter sleeve relative to the jig arm to fully seat the screw, as thescrew head may slightly longitudinally displace due to seating in adynamic compression holes; however, the sleeve should remain within thesoft tissue to protect the soft tissue from the torque driver. Once thescrew is seated, and the torque driver removed, the outer sleeve isremoved from engagement with the jig arm 1102.

The above steps are repeated as necessary for each threaded screw holeand compression screw hole receiving a bone screw. Finally, referringback to FIGS. 40 and 42, a hole is drilled through the bore 1150 of thelocking guide 1130, and then the locking guide is unscrewed from the jig1100 so that the jig is disassembled from the plate 1010 a. The outersleeve 1200 is advanced into the position formerly occupied by thelocking guide 1130, and a bone screw is advanced to the plate 1010 a anddriven into the plate and bone to complete the implantation.

There have been described and illustrated herein embodiments of asystem, devices, and methods relating to periprosthetic fracturefixation. While particular embodiments of the invention have beendescribed, it is not intended that the invention be limited thereto, asit is intended that the invention be as broad in scope as the art willallow and that the specification be read likewise. Thus, it isspecifically intended that various features described with respect todifferent embodiments of the compression plates, cable securingstructure, and crimp lugs be usable interchangeably in other plates, andspecifically in plates combining a plurality of the described features,as such structure permits. Further, while the plates and systems havebeen specifically described with respect to fixation and stabilizationat the femur, it is appreciated that such plates or like plates ofsuitable size and shape can be adapted for periarticular fixation ofother long bones. Moreover, while the features herein have beendescribed in the context of periarticular fixation, it is appreciatedthat the structure and use is not limited thereto, and may haveadditional utility particularly in other areas of orthopedic fixation,other surgical procedures, and even non-medical applications. It willtherefore be appreciated by those skilled in the art that yet othermodifications could be made to the provided invention without deviatingfrom its spirit and scope as claimed.

What is claimed is:
 1. A cable tensioner for applying tension to a cablerelative to a plate or cable securing structure, said cable tensionercomprising: a) a tube having a proximal end and a distal end; b) agearbox coupled to said proximal end of said tube, said gearboxincluding, a worm screw, a drive gear in engagement with said wormscrew, and a cable pulley rotationally fixed to said drive gear androtatable about a pulley axis, said cable pulley including structure toengage the cable, a cable passage being defined transverse to saidpulley axis, wherein when the cable is placed through said tube, oversaid pulley, and through said cable passage, and said tube is advancedover the cable such that said distal end of said tube is contactedagainst the plate or the cable securing structure with which the cableis used, rotation of said drive gear operates to pull the cable intotension; and c) a cable tension lock removably engaged to the gearbox,the cable tension lock configured to lock and unlock an applied tensionon the cable, wherein said gearbox is removable relative to said cabletension lock while said cable tension lock holds an applied tension onthe cable.
 2. A cable tensioner according to claim 1, furthercomprising: a knob coupled relative to said pulley, wherein rotation ofsaid knob in one direction operates to increase resistance on saidpulley, and rotation of said knob in an opposite second directionoperates to decrease resistance on said pulley.
 3. A cable tensioneraccording to claim 2, wherein: said cable passage is defined throughsaid drive gear, said pulley and said knob.
 4. A cable tensioneraccording to claim 3, wherein: said cable pulley has a tubular shaft atleast partially defining said cable passage.
 5. A cable tensioneraccording to claim 2, wherein: said knob and said pulley are located onopposite sides of said drive gear.
 6. A cable tensioner according toclaim 2, wherein: said knob and said pulley are located on oppositesides of said worm screw.
 7. A cable tensioner according to claim 1,wherein: said worm screw has a proximal torque driver socket.
 8. A cabletensioner according to claim 1, wherein: said pulley defines acircumferential cable track having a sidewall, and said structure toengage the cable includes at least one groove opening in said sidewallof said track.
 9. A cable tensioner according to claim 8, wherein: saidpulley includes a guide structure located at said groove for guiding thecable from said groove of said cable track into said cable passage. 10.A cable tensioner according to claim 1, wherein: said distal end of saidtube is curved.
 11. A cable tensioner according to claim 1, wherein:said proximal end of said tube is releasable from said gearbox.
 12. Acable tensioner according to claim 1, in association with: a flexibleinelastic cerclage cable having a first end provided with a stop and asecond end, said cable extending through said tube, about a portion ofsaid pulley and through said cable passage.
 13. A cable tensioneraccording to claim 1, further comprising: a tension gauge indicating anamount of tension applied to the cable.
 14. A cable tensioner accordingto claim 13, further comprising: a spring coupled between said tube andsaid tension gauge, wherein displacement of said spring is related tosaid amount of applied tension.
 15. A cable tensioner according to claim1, wherein: said cable tension lock includes a cam lock that acts on thecable.
 16. A cable tensioner for applying tension to a cable relative toa plate or cable securing structure, said cable tensioner comprising: a)a tube having a proximal end and a distal end; b) a handle coupled tosaid proximal end of said tube and having a movable portion and astationary portion, said movable portion rotatable about a first axisrelative to said stationary portion, said handle defining a cablepassage that has a second axis transverse to said first axis, whereinsaid handle is configured to receive said cable along the second axis,and wherein rotation of said movable portion relative to said stationaryportion operates to pull the cable within said cable passage intotension; c) a spring coupled between said proximal end of tube and adistal end of said handle, wherein displacement of said spring isrelated to said amount of applied tension; d) a tension gauge coupled tosaid spring and between said spring and said distal end of said handle,said tension gauge indicating an amount of tension applied to the cable;and e) a cable tension lock that locks an applied tension on the cable.17. A cable tensioner according to claim 16, wherein: said spring, saidtension gauge, and said cable tension lock are together separable fromsaid handle.
 18. A cable tensioner for applying tension to a cablerelative to a plate or cable securing structure, said cable tensionercomprising: a) a tube having a proximal end and a distal end; and b) agearbox coupled to said proximal end of said tube, said gearboxincluding, a worm screw, a drive gear in engagement with said wormscrew, and a cable pulley rotationally fixed to said drive gear androtatable about a pulley axis, said cable pulley including structure toengage the cable and having a tubular shaft, a knob coupled relative tosaid pulley and threadedly engaged to said tubular shaft, whereinrotation of said knob in one direction operates to increase resistanceon said pulley, and rotation of said knob in an opposite seconddirection operates to decrease resistance on said pulley, a cablepassage being defined through said drive gear, said tubular shaft ofsaid pulley, and said knob, and transverse to said pulley axis, whereinwhen the cable is placed through said tube, over said pulley, andthrough said cable passage, and said tube is advanced over the cablesuch that said distal end of said tube is contacted against the plate orthe cable securing structure with which the cable is used, rotation ofsaid drive gear operates to pull the cable into tension.